It is known to form fuel tanks using an extrusion blow-moulding process. The fuel tanks are formed as a sealed moulding and access apertures are cut to allow the installation of functional components, such as fuel pumps, vents and fuel level senders. To reduce the potential emission of hydrocarbons from the fuel, it is desirable to reduce the number of access apertures formed in the fuel tank. However, this can make it difficult to install the required functional components within the fuel tank.
It is known from GB 2428415 to provide a moveable carrier on a suspension arm. A peg is molded into a sidewall of the fuel tank to support a distal end of the suspension arm. The carrier supports a fuel sender unit and is initially in an installation position to enable it to be introduced through the access aperture. The carrier is then pivoted to a deployed position by the mounting peg when the suspension arm is installed. A proximal end of the suspension arm is supported by a flange located in an access aperture.
Furthermore, U.S. 2008/0149199 discloses an articulated boom for positioning a fuel line in a saddle-type fuel tank. The boom has a spring-loaded mechanism which enables the boom to pivot from a first pressure-loaded position to a second pressure-loaded position by pulling on the fuel line. The proximal end of the boom is mounted on a swirl tank provided in the fuel tank. A retainer provided on the boom presses against the floor of the tank and a support member engages the roof of the tank to fix the boom in position.
A potential problem with these systems is the need to mount other functional components, such as a fill limiter and fuel level sender, within the fuel tank. One approach is to attach the functional components to a mounting flange positioned in the access aperture. For example, U.S. Pat. No. 7,520,293 discloses mounting a manifold in the access aperture to support a tentacle connected to a floating vent valve. Similarly, U.S. Pat. No. 6,298,540 discloses a fuel level sender unit mounted in the access aperture of a fuel tank. GB 2428415 discloses mounting a fuel tank venting device on the suspension arm. However, these approaches may apply increased loads to the mounting flange (directly or indirectly) and may reduce the efficacy of seals formed around the access aperture.
It is known to provide a fuel tank with a fill limiter to limit the amount of fuel that can be introduced into the fuel tank. The fuel fill limiter typically comprises a valve which selectively opens and closes a breather vent to allow air to vent from the fuel tank when fuel is being supplied. The valve is typically actuated by a float provided within the fuel tank and, when the level of the fuel in the fuel tank reaches a predetermined height, the valve closes the breather vent and seals the fuel tank. A venturi disposed within the fuel dispenser cuts off the supply of fuel in response to the resulting increase in pressure within the fuel tank.
It may be necessary to service or replace the fuel fill limiter valve. As the valve may be disposed within the fuel tank, this can involve at least partially dismantling the fuel tank.